Citation tracking and citation analysis is facilitated by making use of online information resources via the Web which specialize in citations and tools for conducting citation analysis. The prolific growth of the online citation resources like Scopus and Google Scholar created new opportunities for academics in citation tracking and citation analysis. This paper presents the results of a comparative study of Web of Science (WOS), Scopus, and Google Scholar (GS) for the South African environmental sciences scholarly journals. The objectives of this study included comparing WOS, Scopus and GS on a macro-level, micro-level, in order to determine whether GS could be considered a substitute for the fee-based citation resources WOS and Scopus. The South African scholarly environmental sciences journals were chosen as the target population. This paper focus on the results of the content verification process which measured amongst others the citation counts, multiple copies and inconsistencies encountered across the three citation resources WOS, Scopus and GS. The results regarding the total citation count of the three citation resources indicated that WOS retrieved the most citation counts. In addition GS retrieved the most multiple copies which included duplicates and triplicates. The study also show that all three citation resources retrieved unique citation hits of which WOS retrieved the most. The study was able to establish that GS is not yet a substitute for WOS and/or Scopus for the South African scholarly environmental sciences journals internationally accredited during the period 2004-2008. It was concluded that GS can be used as a supplementary citation resource to the fee-based citation resources WOS and Scopus.